docker 中的 django 未检测到 SIGINT

Question

This is a funny stackover flow question, because I have an answer, but the answer is a few years old. I can't find much content which is new, yet it seems like it would be quite high profile.

I am using docker-compose to start a few containers. Two of them use standard postgres and redis images. The others are django 2.2.9 (and celery) This is a development environment, and I start them with docker compose, like this:

  command: ./manage.py runserver 0.0.0.0:80

docker-compose stop sends a SIGINT. The redis and postgres containers exit quickly. the django containers don't. docker-compose stop loses patience and kills them.

(and pycharm has infinite patience currently, and doesn't send a kill until I force it).

This post from 2015 referring to Django 1.9 ( http://blog.lotech.org/fix-djangos-runserver-when-run-under-docker-or-pycharm.html ) says that

"The quick fix is to specifically listen for SIGINT and SIGTERM in your manage.py, and sys.kill() when you get them. So modify your manage.py to add a signal handler:"

and it says how. The fix to change manage.py to catch SIGINT works and it's a handful of lines, although it doesn't work for celery which has its own startup. So I can carry forward my own version of of manage.py and fix celery, but really is this still how to fix this?

I see the the dockerfile could have

STOPSIGNAL SIGINT

but it doesn't make and difference, I suppose because the entry point is managed by docker-compose.

Answer 1

Use the list variant of command :

command: ["./manage.py", "runserver", "0.0.0.0:80"]

See https://hynek.me/articles/docker-signals/ for details why.